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Full-Text Articles in Biomechanics
The Roles Of Morphology And Posture On Gait Mechanics, Russell T. Johnson
The Roles Of Morphology And Posture On Gait Mechanics, Russell T. Johnson
Doctoral Dissertations
Humans walk with an upright posture, extended limbs during stance, and a double-peaked vertical ground reaction force. Our closest living relatives, chimpanzees, sometimes walk bipedally but do so with a flexed, abducted hind limb. Previous researchers have studied humans walking with a crouched, chimpanzee-like gait pattern to try to infer how extinct human ancestors walked. However, it is not clear if the way humans perform this crouched posture gait would be similar to the way a species that is adapted to walk with a crouched posture would walk. The purpose of this dissertation was to investigate the impact of morphology …
Physical Activity And Age-Related Mechanical Risk Factors For Knee Osteoarthritis, Jocelyn F. Hafer
Physical Activity And Age-Related Mechanical Risk Factors For Knee Osteoarthritis, Jocelyn F. Hafer
Doctoral Dissertations
Knee osteoarthritis is an age-related disease which will affect nearly 50% of individuals in their lifetime. Because there are currently no treatments to substantially slow the progression of this disease, it is important to identify mechanisms to reduce the risk of osteoarthritis initiation. Osteoarthritis is a disease which is at least partially mediated by mechanical factors which may result from age-related changes in gait. The extent to which habitual physical activity can modify the impact of age on gait, knee mechanics, and thus cartilage loading is unknown. The aim of this dissertation was to examine the effects of age and …
Burrowing And Walking Mechanisms Of North American Moles, Yi-Fen Lin
Burrowing And Walking Mechanisms Of North American Moles, Yi-Fen Lin
Doctoral Dissertations
Moles (Family Talpidae) are a classic example of extreme specialization, in their case highly derived forelimb morphologies associated with burrowing. Despite many observations of mole burrows and behaviors gathered in the field, we know very little about how and how well moles use their forelimbs to dig tunnels and to walk within the built tunnels to collect and transport food. The first chapter investigates the effect of soil compactness on two sympatric mole species under controlled laboratory conditions. My results demonstrate that increasing soil compactness impedes tunneling performance as evidenced by reduced burrowing speed, increased soil transport, shorter tunnels, shorter …
The Consequences Of Speed: Studies Of Cavitation During The Mantis Shrimp Strike And The Control Of Rapid Deceleration During Toad Landing, Suzanne M. Cox
The Consequences Of Speed: Studies Of Cavitation During The Mantis Shrimp Strike And The Control Of Rapid Deceleration During Toad Landing, Suzanne M. Cox
Doctoral Dissertations
There are consequences of moving quickly in this world. Here we investigate how two very different species, mantis shrimp (Odontodactylus scyllarus) and cane toads (Bufo marinus), negotiate forces that result from moving rapidly in different environments. To study the mechanical principles and fluid dynamics of ultrafast power-amplified systems, we built Ninjabot, a physical model of the extremely fast mantis shrimp. While mantis shrimp produce damaging cavitation upon impact with their prey, they do not cavitate during the forward portion of their strike despite extreme speeds. In order to study cavitation onset in non-linear flows common during …